The mammalian iris often is described as a camera shutter-like device charged with regulating the illumination presented to the retina. In primates, iris (and pupil opening) function overtly is tightly yoked to the twin constrains of ambient light and accommodative state. The primate model is not an efficient environment in which to find an optical role for the iris beyond something obvious such as the depth of field gain achieved with a pinhole. However, other mammals have irides that obviously could participate in the optical delivery of information to the retina. For instance, a single eye in many Grandorder Ungulata species shows a double pinhole pupil at miosis. Features such as double pinholes are not well understood optically or anatomically. The current study proposes to identify the anatomical aspects of some irides having double pinholes at miosis and then applying that information to the study of the more regionally homogenous primate iris. Since minority university environments usually do not support high technology science, the focus of the current study is to establish a functional but technologically limited image description facility. Once established, the image description workplace will be used to describe iris features in eyes selected from the 930 eye/150 species eye collection maintained by the Comparative Ocular Anatomy Laboratory (COAL). The image description workplace will emphasize a multimedia-type of interaction between a computer-based image analysis system and a high resolution live color video image of portions of iris sections from series (ontogenic) of eyes. Regional (superior, nasal, inferior, temporal) samples of the irides of three ungulate species (spotted dolphin, dall sheep, sitatunga) having the potential for a double pinhole pupil will be analyzed for iris feature abundance. Two micron-thick sections will be collected from about 100 microns (50 sections) of each of five subsamples of each major region. Three sections in each of the five subsamples will be randomly chosen for evaluation using an Olympus BH-2 light microscope having a Javelin JE3462 high resolution CCD color camera mounted at the trinolcular and connected to a Sony 127IQ high resolution monitor. The iris in a given section will be sequentially photographed along its length and each image will be acquired by a frame capture board and filed in a hard drive at the computer. Iris components of interest (dilator, sphincter, dilator to sphincter spurs, nerves, blood vessels, iris pigmented epithelium and stroma) will be analyzed in each video frame. Data for each iris section will then be collated and compared statistically with other data from the same region. Then, regional summaries will be compared and a quantitative analysis of regional variation will be generated. Developing the image description workplace and then characterizing the regional variation of the iris in the three ungulate species will consume the bulk of the three years of proposed study. However, in the third year, the techniques developed in this research will be applied to a study of the rhesus monkey irides to see if similar functional antomy cues can be identified in the primate iris.